Consolidated Statements of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue and cost of goods sold
Hydrocarbon revenue	$ 451	$ 192	$ 1,462	$ 1,449
Grant and other revenue	130	274	627	787
Total revenues	6,944	8,017	21,377	22,840
Cost of goods sold	9,650	10,629	28,862	29,761
Gross loss	(2,706)	(2,612)	(7,485)	(6,921)
Operating expenses
Research and development expense	1,156	1,527	3,670	5,014
Selling, general and administrative expense	2,273	5,135	6,337	13,406
Total operating expenses	3,429	6,662	10,007	18,420
Loss from operations	(6,135)	(9,274)	(17,492)	(25,341)
Other (expense) income
Interest expense	(2,100)	(2,121)	(6,497)	(6,186)
(Loss)/Gain on exchange or conversion of debt	(920)		(920)	285
(Loss)/Gain on extinguishment of warrant liability	5		(918)	1,775
(Loss)/Gain from change in fair value of the 2017 Notes	(1,854)	157	(3,629)	3,582
(Loss)/Gain from change in fair value of derivative warrant liability	1,154	4,719	(4,171)	(2,361)
Loss on issuance of equity			(1,519)
Other income	1		207	14
Total other expense, net	(3,714)	2,755	(17,447)	(2,891)
Net loss	$ (9,849)	$ (6,519)	$ (34,939)	$ (28,232)
Net loss per share - basic and diluted	$ (0.10)	$ (0.39)	$ (0.62)	$ (2.22)
Weighted-average number of common shares outstanding - basic and diluted	96,753,965	16,688,632	56,285,311	12,700,844
Ethanol
Revenue and cost of goods sold
Sales	$ 6,363	$ 7,551	$ 19,288	$ 20,604